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Association between testosterone and cancers risk in women: a two-sample Mendelian randomization study
Zhizhou Li1, Maoyu Wang1, Meimian Hua1
1Department of Urology, Shanghai Changhai Hospital, Naval Medical University, Shanghai, China.
Discover Oncology
|November 4, 2023
Summary
This Mendelian randomization study found that higher bioavailable testosterone (BT) and total testosterone (TT) levels causally increase the risk of breast and endometrial cancers in women. BT also showed a causal link to reduced ovarian cancer risk.
Area of Science:
- Endocrinology
- Oncology
- Genetic Epidemiology
Background:
- Observational studies suggest a link between testosterone and cancer risk.
- Causal associations between female testosterone levels and cancer types remain unclear.
Purpose of the Study:
- To investigate the causal relationship between total testosterone (TT) and bioavailable testosterone (BT) and cancer risk in females.
- Utilizing a Mendelian randomization approach to address confounding factors.
Main Methods:
- Two-sample Mendelian randomization analysis was performed.
- Instrumental single nucleotide polymorphisms (SNPs) associated with testosterone levels were identified.
- Inverse-variance weighted (IVW) method was the primary analytical approach, with sensitivity analyses for robustness.
Main Results:
- Positive causal links were found between BT and breast cancer (OR=1.14) and endometrial cancer (OR=1.46).
- Positive causal links were found between TT and breast cancer (OR=1.18), cervical cancer (OR=1.002), and endometrial cancer (OR=1.41).
- A negative causal relationship was observed between BT and ovarian cancer (OR=0.86).
Conclusions:
- Testosterone plays a causal role in the development of breast, endometrial, ovarian, and cervical cancers in women.
- Potential, though weak, associations with bladder and thyroid cancer were noted.
- No significant causal links were identified between testosterone and other female cancers.
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